VME Backplanes for Military & Defense Applications

The VME or VMEbus standard is well-established for backplane designs, and is widely found in military, defense and aerospace computing systems.

VME Backplane Dimensions & Design

VME backplanes are designed to accommodate Eurocard-format plug-in cards that are either 3U or 6U in height, with capacities of up to 21 slots. Hybrid backplanes may also combine VME slots with support for plug-in modules from other standards such as VPX.

These backplanes utilize a parallel bus structure, and the data bus may be 16, 32 or 64 bits in width depending on the VME technology revision used. VME also uses a master/slave architecture where all modules are designated as one or the other, either controlling the bus or responding to commands from other modules.

VME64x Backplanes

VME64X rugged backplane by Atrenne

The VME standard has been revised several times in order to allow VME computing systems to keep up with the demands for more advanced technological capabilities.

VME64 was the first revision to introduce a 64-bit data bus, thus enabling larger bandwidths and faster data transfer speeds. It also introduced 64-bit addressing for 6U boards, allowing VME64 backplanes to utilize modules with more powerful processors and larger memory spaces.

A further revision, known as VME64x, added the ability to hot-swap plug-in cards and modules, making it ideal for computing systems that need to be quickly reconfigured for different mission requirements. These can also support all VME and VME64 modules.

Applications & Ruggedization

This type of backplane is utilized in VME chassis and computing systems designed for a wide variety of military and defense applications, including command and control, radar, avionics, armored vehicles and signal processing.

Ruggedization methods for defense-specific VME backplanes may include extra stiffness to prevent damage due to high levels of shock and vibration, and conduction cooling designs that allow excess heat to be removed from the board into the chassis or a heat exchanger system.